Periodontal disease is possibly the most common disease known to man, and is said to affect three-quarters of the adult population. Loss of periodontal tissue due to periodontal disease is the principal cause of tooth loss in adulthood. Periodontal tissue loss may result from infectious disease (e.g., bacterially-induced gingivitis), nutritional disease, (e.g., scurvy), or neoplastic conditions. Typically, tissue loss is accompanied by inflammation, bleeding and ulceration. Without treatment, periodontal tissue loss loosens the tooth and ultimately may cause loss of the tooth and the alveolar bone tissue (periodontitis).
Gingivitis and periodontal disease cause enlargement of the periodontal pocket (gingival sulcus) of the affected tooth. The pocket observed in diseased gingiva is much deeper than the normal sulcus. This enlarged pocket is difficult to clean with either a tooth brush or floss and, consequently, bacteria and plaque accumulate within the pocket, causing further enlargement of the pocket. Eventually, the periodontal ligament and supporting alveolar bone are destroyed, leading to loss of the tooth.
To permit effective treatment of periodontitis, it is essential to identify the presence and severity of active periodontal disease within a periodontal pocket. Even deep periodontal pockets do not necessarily correlate with the presence of active periodontal disease and, accordingly, traditional methods of measuring pocket depth may not provide an accurate indicator of the progression of the disease. Clearly, a more accurate means of determining the presence and extent of active periodontal disease is greatly to be desired.
It therefore is an object of this invention to provide methods of diagnosing periodontal disease. It is a further object of the invention to provide kits for diagnosing periodontal disease.
In accomplishing the foregoing objects, there has been provided, in accordance with one aspect of the present invention, a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of a protein in individual gingival crevicular fluid (GCF) samples obtained from one of various sites of a patient, wherein said protein is selected from the group consisting of (i) tissue-type plasminogen activator (t-PA) and (ii) plasminogen activator inhibitor-2 (PAI-2); and (b) obtaining the mean level of said protein in the GCF and using the mean level to diagnose periodontal disease.
In accordance with another aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of a protein in individual gingival crevicular fluid (GCF) samples, each sample obtained from one of various sites of a patient, the protein selected from the group consisting of (i) tissue-type plasminogen activator (t-PA) and (ii) plasminogen activator inhibitor-2 (PAI-2); and (b) comparing the levels of the protein in the samples from the various sites, a statistically significant variation of the levels among the various sites indicating a diagnosis of periodontal disease.
In accordance with still another aspect of the invention, there is provided a method of diagnosing periodontal disease, the method comprising the steps of:
(a) determining the level of tissue-type plasminogen activator (t-PA) in individual gingival crevicular fluid (GCF) samples obtained from a plurality of sites of a patient; and (b) obtaining the mean of the level of t-PA in the GCF and using the mean level to diagnose periodontal disease. In one embodiment, the method may further comprise comparing the mean of the t-PA level in the GCF from the patient with a predetermined mean of the t-PA level in the GCF from a healthy individual, wherein a statistically significant increase of the mean level of the t-PA level in the GCF indicates the presence of periodontal disease.
In accordance with yet another aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of tissue-type plasminogen activator (t-PA) in individual gingival crevicular fluid (GCF) samples obtained from a plurality of sites of a patient; and (b) comparing the levels of t-PA in the samples from the various sites, wherein a statistically significant variation of the t-PA levels among the various sites indicates the presence of periodontal disease.
In accordance with still another aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of plasminogen activator inhibitor-2 (PAI-2) in individual gingival crevicular fluid (GCF) samples obtained from a plurality of various sites of a patient; and (b) obtaining the mean of the level of PAI-2 in the GCF and using the mean level to diagnose periodontal disease. In one embodiment, step (b) may further comprise comparing the mean of the PAI-2 level in the GCF from the patient with a predetermined mean level of PAI-2 in the GCF from a healthy individual, wherein a statistically significant increase of the mean of the PAI-2 level in the GCF indicates the presence of periodontal disease.
In accordance with a further aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of plasminogen activator inhibitor-2 (PAI-2) in individual gingival crevicular fluid (GCF) samples, each sample obtained from one of various sites of a patient; and (b) comparing the levels of PAI-2 in the samples from the various sites, wherein a statistically significant variation of the PAI-2 levels among the various sites indicates the presence of periodontal disease.
In accordance with yet another aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the level of tissue-type plasminogen activator (t-PA) and the level of plasminogen activator inhibitor-2 (PAI-2) in individual gingival crevicular fluid (GCF) samples obtained from a plurality of various sites of a patient; and (b) obtaining the respective mean of the t-PA levels and the PAI-2 levels in the GCF and using the mean levels to diagnose periodontal disease.
In one embodiment, the respective means of t-PA and PAI-2 levels in the GCF from the patient are compared respectively with predetermined means of the t-PA levels and the PAI-2 levels in the GCF from a healthy individual, wherein a statistically significant increase of both mean levels in the GCF indicates the presence of periodontal disease.
In accordance with a further aspect of the invention, there is provided a method of diagnosing periodontal disease, comprising the steps of: (a) determining the respective level of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-2 (PAI-2) in individual gingival crevicular fluid (GCF) samples obtained from a plurality of sites of a patient; and (b) comparing the t-PA levels of the various sites with each other, and the PAI-2 levels of the various sites with each other, where a statistically significant elevation of both the t-PA levels and the PAI-2 levels among the various sites indicates the presence of periodontal disease.
In a particular embodiment of each of the aspects of the invention described above, the GCF is collected locally from two or more sites of the patient. In another embodiment, the GCF is collected locally from sites selected from the group consisting of the mesial sites, and the buccal and labial sites on the lower teeth. In still another embodiment, the level of the compound is determined using an enzyme-linked immunosorbent assay. In a further embodiment, step (b) further comprises comparing the mean level of the protein in the GCF from the patient with a predetermined mean level of the protein in the GCF from a healthy individual, where a statistically significant increase of the mean level of the protein in the GCF indicates the presence of periodontal disease.
In accordance with still another aspect of the invention there is provided a diagnostic kit for detecting periodontal disease comprising: (a) at least one antibody that binds selectively to an antigen selected from the group consisting of (i) tissue-type plasminogen activator (t-PA) and (ii) plasminogen activator inhibitor-2 (PAI-2); (b) at least one control standard of a known concentration of the antigen; and c) a suitable container. In one embodiment, the kit further comprises a testing format capable of quantitatively determining the concentration of the antigen using the antibody. In another embodiment, the testing format of the kit is an enzyme-linked immunosorbent assay format. In still another embodiment, the kit further comprises a means for collecting gingival crevicular fluid locally. In a further embodiment, the means for collecting gingival crevicular fluid utilizes an absorbent material, preferably a filter paper.
Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.